When the theater is not full, nor is getting full, no person from Party A should sit in the seat right next to any person from another Party B. If I am with somebody, and you do not know me, why are you sitting by me too?! This is crazy. Do some people just need to have a person on both sides of them?
This happened to me yesterday and it almost ruined the movie for me.
On a side note: the 1 time I laughed in the movie was incidentally when nobody else laughed. Come on! Isn't a random punch in the face funny anymore?!